Sidewalk-elevator door.



J. S. UNDHOLM.

SIDEWALK ELEVATOR DOOR.

' APPLICATION FILED FEB. 15, 1916.

Patented J an. 2, 1917.

J ENS S. LINDI-IOLIVI, OF BROOKLYN, NEW YORK.

SIDEWALK-ELEVATOR DOOR.

Specification of Letters Patent.

Patented J an. 2, 1917.

Original application filed September 22, 1915, Serial No. 51,923.Divided and this application filed February To all whom it may concern:

Be it known that I, Jens S. LINDHOLM, citizen of the Danish Monarchy,and resident of Brooklyn, in the county of Kings and State of New York,have invented certain new and useful Improvements in Sidewalk-ElevatorDoors, of which the following is a specification.

This invention relates to improvements in sidewalk elevator doors andthe object of the invention is to provide means for preventingaccidental and untimely opening of the doors for covering the elevatorshaft below the sidewalk.

More specifically the invention provides means for automatically closingthe side walk doors when and as the elevator descends below the sidewalkand whereby the doors remain closed when the elevator is wholly belowthe sidewalk level. At the same time the means referred to does notprevent the doors from being opened partially by raising the elevator aslight distance above the sidewalk to admit light and air to the spacebelow the same.

This application is a division of my allowed application Serial Number51,923, filed September 22, 1915.

ith the above and other objects in view the invention is embodied in amechanism arranged and constructed as hereinafter set forth and claimedand as illustrated in'the accompanying drawing in which Figure lis asectional view of a sidewalk elevator equipped with a door mechanismembodying this invention. Figs. 2, 3 and 4 are enlarged detail views ofthe parts shown in Fig. 1. Fig. 5 is a detail view showing a modifiedconstruction employed when the elevator travels a relatively greatdistance below the sidewalk.

Referring to the drawing 10 represents the elevator which may be of anywell known construction having the frame work 18 and the bow irons 19.The elevator moves in the shaft 13 and 21 represents the hoistingapparatus. The shaft 13 is generally closed by the sidewalk doors 14 and15 pivoted at 16. In order to compel the doors to close when theelevator descends there are provided in the shaft 13 the sheaves 40, 41,42 and 43. The rope 44 secured to the door 14 passes over the sheaves 40and 41, and the rope 45 secured to the door 15 passes over the sheaves42 and 43. The two ropes Serial No. 78,366.

are joined in one rope 46 to which there is yleldingly secured a weight47 which moves in guides 48 secured to the wall of the shaft.

To the bottom of the weight 47, which serves to keep the ropes taut,there is pivoted a dog 49 having a tail piece 50. lVhen the doors areopen the position of the dog 49 is as shown in Fig. 4. After the descentof the elevator and when the doors begin to close, the lower end of thebow iron 18 strikes the dog and pulls the weight 47 down with the doorropes, thereby compelling the doors to follow the bow of the irons andclose, the tail piece of the dog sliding against the guide 48 as shownin Fig. 4. When the doors have closed the dog will have reached a recess51 in the wall of the shaft 13 into which the tail piece will slide andthe dog will turn on its pivot 53 as shown in Fig. 2.

The dog will now remain in this position during the further continueddescent of the elevator as is obvious, because the bow iron slidesagainst the dog and consequently the doors cannot open until on theascent of the elevator the lower end of the bow iron passes above thedog and when the upper end of the iron strikes the doors pulls the dogout of the recess and permits the weight and the dog to rise. In casethe shaft is longer than the height of the bow iron, there will beprovided a second or more dogs 54 in the well connected by a link 55 tothe upper dog as shown in Fig. 5 and whereby the dogs will remain turneddownward and the doors closed during the descent of the elevator.

From the foregoing it is clear that the doors remain closed while theelevator is below the sidewalk and cannot be accidentally opened. Alsothat the doors open and close with the movements of the elevator andthat the length of the travel of the latter is immaterial with respectto the operation of the door closing and locking mechanism.

The invention is susceptible of changes and modifications and I claimall variations, changes and modifications which properlv come within theprinciple of the invention and the scope of the appended claims.

I claim 1. The combination with a sidewalk elevator shaft and sidewalkdoors therefor, an elevator movable within said shaft and means operatedby said elevator for pre venting accidental opening of the said sidewalkdoors.

2. The combination with a sidewalk elevator shaft and sidewalk doorstherefor, and

means including the elevator operated in said shaft for preventing thesaid doors from being opened by means other than the said elevator andfor closing the said doors when the elevator descends.

8. The combination with a sidewalk e1evator shaft and sidewalk doorstherefor, an elevator operated the length of said shaft, means on saidelevator for opening the said Copies of this patent may be obtained fordoors on the ascent of the elevator, and means in said shaft andconnected to the said doors for closing the latter by the said elevatoras it descends and for maintaining said doors closed during the entiredescending movement of the elevator below the sidewalk level.

Signed at New York, inithe county of New York and State of New York,this 20 11th day of February A. D. 1916.

J S. LINDHOLM.

five cents each, by addressing the Commissioner of Patents,

Washington, D. G.

